Management of liver transplantation in a patient with a history of heparin-induced thrombocytopenia

Abstract

Heparin-induced thrombocytopenia (HIT) is an adverse immune-mediated drug reaction in which antibodies are generated usually towards complexes of the soluble platelet protein platelet-factor-4 (PF4) and heparin. The resulting immune complexes activate platelets intravascularly, which increases the generation of thrombin. Therefore, HIT is strongly associated with thrombosis and heparin is thought to be contraindicated. As HIT antibodies decline rapidly in titre, short-term re-exposure to heparin is feasible in special situations. We report an uneventful liver transplantation of a heparinized donor in a patient with a 20-month history of HIT. Before, 2, 5, 12 and 25 days after transplantation, the patient's blood was drawn for analysis of heparin-induced antibodies by a functional assay (HIPA) and by an antigen assay (PF4-heparin/ELISA). Lepirudin was used for postoperative anticoagulation. Apart from hepatic artery bleeding, the clinical course was uncomplicated, neither thrombocytopenia nor thromboembolic complications occurred. Weak heparin-induced platelet activation, caused by pre-existing HIT antibodies was detected before and 12 days after transplantation by the HIPA test; moreover borderline amounts of anti-PF4-heparin antibodies were found. Twenty months after an episode of HIT, a patient may receive an organ from a heparin-treated donor without risk of thrombocytopenia or thromboembolic complications. Avoidance of heparin for postoperative anticoagulation is recommended.